f2fs: use pagevec_lookup_range_tag()

We want only pages from given range in f2fs_write_cache_pages().  Use
pagevec_lookup_range_tag() instead of pagevec_lookup_tag() and remove
unnecessary code.

Link: http://lkml.kernel.org/r/20171009151359.31984-6-jack@suse.cz
Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/f2fs/data.c

@@ -1669,8 +1669,8 @@ retry:
 	while (!done && (index <= end)) {
 		int i;
 
-		nr_pages = pagevec_lookup_tag(&pvec, mapping, &index, tag,
-			      min(end - index, (pgoff_t)PAGEVEC_SIZE - 1) + 1);
+		nr_pages = pagevec_lookup_range_tag(&pvec, mapping, &index, end,
+				tag, PAGEVEC_SIZE);
 		if (nr_pages == 0)
 			break;
 
@@ -1678,11 +1678,6 @@ retry:
 			struct page *page = pvec.pages[i];
 			bool submitted = false;
 
-			if (page->index > end) {
-				done = 1;
-				break;
-			}
-
 			done_index = page->index;
 retry_write:
 			lock_page(page);